Beefed up the tests for multi-cache handling of the cache middleware and view decorators, and made a couple of tweaks for edge cases as a result.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@15021 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Russell Keith-Magee 2010-12-22 07:52:44 +00:00
parent 0fef92f6f0
commit b22415214a
3 changed files with 181 additions and 22 deletions

View File

@ -85,7 +85,7 @@ class UpdateCacheMiddleware(object):
return response
patch_response_headers(response, timeout)
if timeout:
cache_key = learn_cache_key(request, response, timeout, self.key_prefix)
cache_key = learn_cache_key(request, response, timeout, self.key_prefix, cache=self.cache)
self.cache.set(cache_key, response, timeout)
return response
@ -120,17 +120,14 @@ class FetchFromCacheMiddleware(object):
return None # Don't cache requests from authenticated users.
# try and get the cached GET response
cache_key = get_cache_key(request, self.key_prefix, 'GET')
cache_key = get_cache_key(request, self.key_prefix, 'GET', cache=self.cache)
if cache_key is None:
request._cache_update_cache = True
return None # No cache information available, need to rebuild.
response = self.cache.get(cache_key, None)
# if it wasn't found and we are looking for a HEAD, try looking just for that
if response is None and request.method == 'HEAD':
cache_key = get_cache_key(request, self.key_prefix, 'HEAD')
cache_key = get_cache_key(request, self.key_prefix, 'HEAD', cache=self.cache)
response = self.cache.get(cache_key, None)
if response is None:
@ -149,28 +146,33 @@ class CacheMiddleware(UpdateCacheMiddleware, FetchFromCacheMiddleware):
using the decorator-from-middleware utility.
"""
def __init__(self, cache_timeout=None, cache_anonymous_only=None, **kwargs):
self.cache_timeout = cache_timeout
if cache_timeout is None:
self.cache_timeout = settings.CACHE_MIDDLEWARE_SECONDS
# We need to differentiate between "provided, but using default value",
# and "not provided". If the value is provided using a default, then
# we fall back to system defaults. If it is not provided at all,
# we need to use middleware defaults.
cache_kwargs = {}
try:
self.key_prefix = kwargs.get('key_prefix')
if self.key_prefix is not None:
cache_kwargs['KEY_PREFIX'] = self.key_prefix
else:
self.key_prefix = ''
except KeyError:
self.key_prefix = settings.CACHE_MIDDLEWARE_KEY_PREFIX
cache_kwargs['KEY_PREFIX'] = self.key_prefix
try:
cache_alias = kwargs.get('cache_alias')
if cache_alias is None:
cache_alias = DEFAULT_CACHE_ALIAS
if cache_timeout is not None:
cache_kwargs['TIMEOUT'] = cache_timeout
except KeyError:
cache_alias = settings.CACHE_MIDDLEWARE_ALIAS
cache_kwargs = {}
try:
key_prefix = kwargs.get('key_prefix')
if key_prefix is not None:
cache_kwargs['KEY_PREFIX'] = key_prefix
except KeyError:
cache_kwargs['KEY_PREFIX'] = settings.CACHE_MIDDLEWARE_KEY_PREFIX
if cache_timeout is None:
cache_kwargs['TIMEOUT'] = settings.CACHE_MIDDLEWARE_SECONDS
else:
cache_kwargs['TIMEOUT'] = cache_timeout
if cache_anonymous_only is None:
self.cache_anonymous_only = getattr(settings, 'CACHE_MIDDLEWARE_ANONYMOUS_ONLY', False)
@ -178,3 +180,4 @@ class CacheMiddleware(UpdateCacheMiddleware, FetchFromCacheMiddleware):
self.cache_anonymous_only = cache_anonymous_only
self.cache = get_cache(cache_alias, **cache_kwargs)
self.cache_timeout = self.cache.default_timeout

View File

@ -21,7 +21,7 @@ import re
import time
from django.conf import settings
from django.core.cache import cache
from django.core.cache import get_cache
from django.utils.encoding import smart_str, iri_to_uri
from django.utils.http import http_date
from django.utils.hashcompat import md5_constructor
@ -162,7 +162,7 @@ def _generate_cache_header_key(key_prefix, request):
key_prefix, path.hexdigest())
return _i18n_cache_key_suffix(request, cache_key)
def get_cache_key(request, key_prefix=None, method='GET'):
def get_cache_key(request, key_prefix=None, method='GET', cache=None):
"""
Returns a cache key based on the request path. It can be used in the
request phase because it pulls the list of headers to take into account
@ -175,13 +175,15 @@ def get_cache_key(request, key_prefix=None, method='GET'):
if key_prefix is None:
key_prefix = settings.CACHE_MIDDLEWARE_KEY_PREFIX
cache_key = _generate_cache_header_key(key_prefix, request)
if cache is None:
cache = get_cache(settings.CACHE_MIDDLEWARE_ALIAS)
headerlist = cache.get(cache_key, None)
if headerlist is not None:
return _generate_cache_key(request, method, headerlist, key_prefix)
else:
return None
def learn_cache_key(request, response, cache_timeout=None, key_prefix=None):
def learn_cache_key(request, response, cache_timeout=None, key_prefix=None, cache=None):
"""
Learns what headers to take into account for some request path from the
response object. It stores those headers in a global path registry so that
@ -199,6 +201,8 @@ def learn_cache_key(request, response, cache_timeout=None, key_prefix=None):
if cache_timeout is None:
cache_timeout = settings.CACHE_MIDDLEWARE_SECONDS
cache_key = _generate_cache_header_key(key_prefix, request)
if cache is None:
cache = get_cache(settings.CACHE_MIDDLEWARE_ALIAS)
if response.has_header('Vary'):
headerlist = ['HTTP_'+header.upper().replace('-', '_')
for header in cc_delim_re.split(response['Vary'])]

View File

@ -14,12 +14,14 @@ from django.core import management
from django.core.cache import get_cache, DEFAULT_CACHE_ALIAS
from django.core.cache.backends.base import InvalidCacheBackendError, CacheKeyWarning
from django.http import HttpResponse, HttpRequest
from django.middleware.cache import FetchFromCacheMiddleware, UpdateCacheMiddleware
from django.middleware.cache import FetchFromCacheMiddleware, UpdateCacheMiddleware, CacheMiddleware
from django.test import RequestFactory
from django.test.utils import get_warnings_state, restore_warnings_state
from django.utils import translation
from django.utils import unittest
from django.utils.cache import patch_vary_headers, get_cache_key, learn_cache_key
from django.utils.hashcompat import md5_constructor
from django.views.decorators.cache import cache_page
from regressiontests.cache.models import Poll, expensive_calculation
# functions/classes for complex data type tests
@ -759,6 +761,15 @@ class LocMemCacheTests(unittest.TestCase, BaseCacheTests):
self.cache = get_cache('locmem://?max_entries=30&cull_frequency=0')
self.perform_cull_test(50, 19)
def test_multiple_caches(self):
"Check that multiple locmem caches are isolated"
mirror_cache = get_cache('django.core.cache.backends.locmem.LocMemCache')
other_cache = get_cache('django.core.cache.backends.locmem.LocMemCache', LOCATION='other')
self.cache.set('value1', 42)
self.assertEquals(mirror_cache.get('value1'), 42)
self.assertEquals(other_cache.get('value1'), None)
# memcached backend isn't guaranteed to be available.
# To check the memcached backend, the test settings file will
# need to contain a cache backend setting that points at
@ -1117,5 +1128,146 @@ class PrefixedCacheI18nTest(CacheI18nTest):
else:
settings.CACHES['default']['KEY_PREFIX'] = self.old_cache_key_prefix
class CacheMiddlewareTest(unittest.TestCase):
def setUp(self):
self.orig_cache_middleware_alias = settings.CACHE_MIDDLEWARE_ALIAS
self.orig_cache_middleware_key_prefix = settings.CACHE_MIDDLEWARE_KEY_PREFIX
self.orig_caches = settings.CACHES
settings.CACHE_MIDDLEWARE_ALIAS = 'other'
settings.CACHE_MIDDLEWARE_KEY_PREFIX = 'middlewareprefix'
settings.CACHES = {
'default': {
'BACKEND': 'django.core.cache.backends.locmem.LocMemCache'
},
'other': {
'BACKEND': 'django.core.cache.backends.locmem.LocMemCache',
'LOCATION': 'other',
'TIMEOUT': '1'
}
}
def tearDown(self):
settings.CACHE_MIDDLEWARE_ALIAS = self.orig_cache_middleware_alias
settings.CACHE_MIDDLEWARE_KEY_PREFIX = self.orig_cache_middleware_key_prefix
settings.CACHES = self.orig_caches
def test_middleware(self):
def view(request, value):
return HttpResponse('Hello World %s' % value)
factory = RequestFactory()
middleware = CacheMiddleware()
prefix_middleware = CacheMiddleware(key_prefix='prefix1')
timeout_middleware = CacheMiddleware(cache_timeout=1)
request = factory.get('/view/')
# Put the request through the request middleware
result = middleware.process_request(request)
self.assertEquals(result, None)
response = view(request, '1')
# Now put the response through the response middleware
response = middleware.process_response(request, response)
# Repeating the request should result in a cache hit
result = middleware.process_request(request)
self.assertNotEquals(result, None)
self.assertEquals(result.content, 'Hello World 1')
# The same request through a different middleware won't hit
result = prefix_middleware.process_request(request)
self.assertEquals(result, None)
# The same request with a timeout _will_ hit
result = timeout_middleware.process_request(request)
self.assertNotEquals(result, None)
self.assertEquals(result.content, 'Hello World 1')
def test_view_decorator(self):
def view(request, value):
return HttpResponse('Hello World %s' % value)
# decorate the same view with different cache decorators
default_view = cache_page(view)
default_with_prefix_view = cache_page(key_prefix='prefix1')(view)
explicit_default_view = cache_page(cache='default')(view)
explicit_default_with_prefix_view = cache_page(cache='default', key_prefix='prefix1')(view)
other_view = cache_page(cache='other')(view)
other_with_prefix_view = cache_page(cache='other', key_prefix='prefix2')(view)
factory = RequestFactory()
request = factory.get('/view/')
# Request the view once
response = default_view(request, '1')
self.assertEquals(response.content, 'Hello World 1')
# Request again -- hit the cache
response = default_view(request, '2')
self.assertEquals(response.content, 'Hello World 1')
# Requesting the same view with the explicit cache should yield the same result
response = explicit_default_view(request, '3')
self.assertEquals(response.content, 'Hello World 1')
# Requesting with a prefix will hit a different cache key
response = explicit_default_with_prefix_view(request, '4')
self.assertEquals(response.content, 'Hello World 4')
# Hitting the same view again gives a cache hit
response = explicit_default_with_prefix_view(request, '5')
self.assertEquals(response.content, 'Hello World 4')
# And going back to the implicit cache will hit the same cache
response = default_with_prefix_view(request, '6')
self.assertEquals(response.content, 'Hello World 4')
# Requesting from an alternate cache won't hit cache
response = other_view(request, '7')
self.assertEquals(response.content, 'Hello World 7')
# But a repeated hit will hit cache
response = other_view(request, '8')
self.assertEquals(response.content, 'Hello World 7')
# And prefixing the alternate cache yields yet another cache entry
response = other_with_prefix_view(request, '9')
self.assertEquals(response.content, 'Hello World 9')
# But if we wait a couple of seconds...
time.sleep(2)
# ... the default cache will still hit
cache = get_cache('default')
response = default_view(request, '10')
self.assertEquals(response.content, 'Hello World 1')
# ... the default cache with a prefix will still hit
response = default_with_prefix_view(request, '11')
self.assertEquals(response.content, 'Hello World 4')
# ... the explicit default cache will still hit
response = explicit_default_view(request, '12')
self.assertEquals(response.content, 'Hello World 1')
# ... the explicit default cache with a prefix will still hit
response = explicit_default_with_prefix_view(request, '13')
self.assertEquals(response.content, 'Hello World 4')
# .. but a rapidly expiring cache won't hit
response = other_view(request, '14')
self.assertEquals(response.content, 'Hello World 14')
# .. even if it has a prefix
response = other_with_prefix_view(request, '15')
self.assertEquals(response.content, 'Hello World 15')
if __name__ == '__main__':
unittest.main()